1. Field of the Invention
The present invention relates to a golf club and more particularly to a golf club which enables the adjustment of inserting depth of a shaft into a hosel.
2. Description of the Related Art
A golf club has a head which is attached to a distal end portion of a shaft. A grip is attached to a proximal end of the shaft.
In a conventional and general golf club head, a hosel hole is provided directly in the head, and a shaft is inserted into the hosel hole to be secured therein by an adhesive. In general, an epoxy based adhesive is used for the adhesive. In replacing shafts, a hosel portion is heated to break the texture of hardened epoxy resin, whereby the shaft can be pulled out of the hosel hole.
In this conventional and general golf club head, the inserting depth of the shaft cannot be changed.
As a golf club which enables the change of inserting depth of a shaft case, JP-A-2010-213859 describes a golf club in which a substantially cylindrical shaft case is secured to a distal end of a shaft, the shaft case is inserted into a hosel in a head from an upper end side of the hosel, and the shaft case is fixed to the hosel by first and second annular screw members which are detachably screwed to the upper end side of the hosel.
In the golf club described in the patent literature, a spacer is interposed between a lower end of the shaft case and a hosel bottom portion, and an internal screw thread is formed in an inner circumferential surface of the upper end side of the hosel. The first screw member is screwed in an upper end of the hosel concentrically with the hosel. An internal screw thread is formed in an inner circumferential surface of an upper end side of the first screw member, and an external screw thread on the second screw member is screwed in the internal screw thread of the first screw member. The inserting depth of the shaft is increased by removing the spacer and the first screw member and screwing the second screw member directly in the internal screw thread of the hosel.
In the golf club described in JP-A-2010-213859, since the inserting depth of the shaft is changed by attaching or detaching the screw member, it follows that the weight of the head changes inevitably in association with the change in the inserting depth of the shaft. An object of the invention is to provide a golf club which eliminates the necessity of attaching or removing a separate member every time the inserting depth of a shaft is changed.
Additionally, in the golf club described in JP-A-2010-213859, since the inserting depth of the shaft is changed by attaching or detaching the screw member, the adjustment of the inserting depth of the shaft is limited to the two stages.